Snapshot Commands
Snapshot commands are used to create snapshots and control/manage snapshot relationships.
Before performing any of the Snapshot commands, snapshot sets must be configured locally on the storage server and the source virtual volume must be mapped to the application server and ready for use. Refer to Getting Started with Snapshot. Refer to Supported Snapshot Set Configurations for valid configurations.
Snapshot commands can be performed using Snapshot Manager or the Command Line Interface (CLI):
Snapshot Manager Commands column – lists commands performed from the Snapshot Manager snap-in.
CLI Commands column – lists commands performed on a single snapshot relationship through a command line. You can use CLI commands for building scripts (or batch jobs) to perform Snapshot activities.
CAUTION: When performing CLI commands, run the command window in Run as Administrator mode.
The table below separates all Snapshot commands into two categories: Snapshot Manager Commands and CLI Commands.
Most Snapshot commands perform the same function, with the only distinctions being:
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whether the command is performed through the Snapshot Manager or command line
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whether the command is initiated from the application server or storage server
To perform Snapshot Manager Commands:
Select a snapshot set in the list and choose the command from the context menu.
The following is an example of a Snapshot CLI command:
EnableSnap DcsSnap#
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EnableSnap describes the action that the particular CLI command performs.
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DcsSnap# is the argument that identifies a snapshot relationship. When using this command, replace # with the actual snapshot relationship number.
In the table below, click a link to view details and syntax for the specific command:
|
Command |
Snapshot Manager Commands |
CLI Commands |
CLI Group Commands |
|
Enable |
Creates a logical image of the source virtual volume on the destination at a specific point in time. The image is instantly available for use, and is independent of the source virtual volume from which it was created. After a snapshot is enabled, additional commands can be performed on it. Note: Once enabled, both the source and the destination may be accessed (Read/Write) at any time. When the destination is accessed, its contents will reflect the data of the source at the particular point in time that the set was enabled, even though the content of the source may have changed. | ||
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Disable |
Disables an existing snapshot relationship. Prohibits any snapshot commands from being performed on the relationship until it is enabled. The state of the destination virtual volume will be undefined unless an established complete image exists for this virtual volume. | ||
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Free NMV Blocks |
Frees NMV storage units allocated to a Snapshot destination virtual volume from an NMV. This command can only be used after disabling, and before re-enabling the snapshot relationship. This function has no effect on destination virtual volumes created from partition-based volumes. | ||
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Discard SAU | |||
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Complete Image |
Copies any data from the source virtual volume that is not already on the destination virtual volume. CI provides a physical copy, that is independent of the source, for the point in time of the Enable or Image Update command. | ||
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Stop Complete Image |
Stops the Complete Image Process on a particular snapshot relationship. | ||
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Stop Complete Image |
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Source Update
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Resynchronizes the snapshot source and destination virtual volumes so that the source volume will become a copy of the current state of the destination and the point in time is updated. | ||
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Stop Source Update |
Stops the Source Update Process on a particular snapshot relationship. | ||
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Stop Source Update |
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Image Update |
Updates the logical image on the destination virtual volume with the latest changes to the source virtual volume and updates the point in time. If an Image Update is performed on a snapshot relationship with a previously performed Complete Image, the CI will be invalid and must be performed again to re-establish the Complete image. (This CI will be completed faster since only the data changed on the source since the last enable or image update was performed on the snapshot relationship will be copied.) | ||
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Start Image Update |
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Stop Image Update |
Stops the Image Update Process on a particular snapshot relationship. | ||
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Stop Image Update |
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Complete Image Delay |
Sets a millisecond delay for the transfer of data associated with the Complete Image process. | ||
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Set Delay… |
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Source Update Delay |
Sets a millisecond delay for the transfer of data associated with the Source Update process. | ||
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Set Delay… |
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Extended Status
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Retrieves the status of the various Snapshot processes, including the percentage difference between the source and destination virtual volumes, the percentage of destination virtual volume completion, and whether a relationship is currently enabled or disabled. | ||
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Last Error
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Retrieves information pertaining to the last Snapshot operation error. | ||
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Status |
Retrieves the status of the various Snapshot processes for a relationship, including whether a relationship is currently enabled or disabled. | ||
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GroupGetStatus | ||
*EnableNewSnap has been phased out and is only maintained for backward compatibility. Use EnableSnap which has the same function as EnableNewSnap.
DataCore Utilities are packaged as an option that you can install on your application server. These application server utilities/commands can be used in the development of scripts for Snapshot operations. Download the DataCore Utilities from the DataCore Technical Support Web site.